A nearby Sun-like star is host to a planet that may be capable of supporting life, according to an international group of astronomers.
The planet is one of five orbiting one of the closest Sun-like stars to Earth, Tau Ceti. It's in a so-called "habitable zone," the region around a star where it's possible for a planet to have enough pressure to maintain liquid water on its surface.
Tau Ceti is 12 light years from Earth and visible to the naked eye in the evening sky.
"This discovery is in keeping with our emerging view that virtually every star has planets, and that the galaxy must have many such potentially habitable Earth-sized planets," said Steve Vogt, a professor of astronomy and astrophysics at the University of California, Santa Cruz.
Tau Ceti's five planets are estimated to have masses between two and six times that of Earth, making it the lowest-mass planetary system yet detected. The planet that lies in its habitable zone has a mass about five times that of Earth's.
"Tau Ceti is one of our nearest cosmic neighbors and so bright that we may be able to study the atmospheres of these planets in the not-too-distant future," said James Jenkins of the Universidad de Chile and a member of the astronomy team.
"Planetary systems found around nearby stars close to our Sun indicate that these systems are common in our Milky Way galaxy," Jenkins added.
The group of astronomers from the U.S., U.K., Chile and Australia, is one of many on the hunt for habitable planets.
Scientists have been using NASA's Kepler Space Telescope to search for Earth-like, habitable planets. The telescope last month wrapped up a three-and-a-half-year prime mission and moved on to an extended four-year plan to continue searching for other worlds.
Since it launched on 2009, the Kepler telescope has searched more than 100,000 stars for signs of Earth-like planets in habitable zones. The telescope has so far confirmed more than 100 such planets.
"The Earth isn't unique, nor the center of the universe," said Geoff Marcy, professor of astronomy at the University of California, Berkeley, in an earlier interview. "The diversity of other worlds is greater than depicted in all the science fiction novels and movies. Aristotle would be proud of us for answering some of the most profound philosophical questions about our place in the universe."
